Media specific feature invocation signaling in enhanced communication systems

Abstract

Subscribers of an enhanced communication system are enabled to indicate invocation or clearing of media specific features such as music-on-hold or video-on-hold. The invocation or clearing is transmitted to participating end points as a Session Initiation Protocol (SIP) re-INVITE message with Session Description Protocol (SDP) attribute descriptions identifying the feature, applicable media channels and whether the message is for invocation or clearing of the feature.

1. A method to be executed at least in part in a computing device for providing media specific features in a unified communication network (UCN), the method comprising:
 receiving an indication of a media specific feature at a first communication application; 
 sending, from the first communication application to a second communication application, an invitation indicating invocation of the media specific feature; 
 receiving, at the first communication application from the second communication application, a confirmation of a capability to perform at least one action associated with the invoked media specific feature at the second communication application; and 
 communicating with the second communication application invoking the media specific feature. 
 
     
     
       2. The method of  claim 1 , wherein an extension of Session Description Protocol (SDP) is employed to communicate the invocation of the media specific feature. 
     
     
       3. The method of  claim 2 , wherein the invitation is sent as a re-INVITE offer employing an SDP session attribute for an established Session Initiation Protocol (SIP) session. 
     
     
       4. The method of  claim 3 , wherein the session attribute is applicable to at least one specified media channel. 
     
     
       5. The method of  claim 2 , wherein the media specific feature is one of: a music-on-hold feature and a video-on-hold feature. 
     
     
       6. The method of  claim 2 , further comprising:
 receiving an indication for clearing an invoked media specific feature at the first communication application; 
 sending another invitation to the second communication application indicating clearing of the invoked media specific feature; and 
 clearing the invoked media specific feature at the second communication application. 
 
     
     
       7. The method of  claim 6 , wherein the other invitation is a re-INVITE offer employing an SDP attribute for each media channel associated with the invoked media specific feature. 
     
     
       8. The method of  claim 1 , wherein the invitation is used by a SIP user agent to render at least one user interface element for notifying a user associated with the second communication application. 
     
     
       9. The method of  claim 1 , wherein the invitation is sent to a plurality of communication applications participating in an established SIP communication session with the first communication application. 
     
     
       10. A system for providing media specific features in a unified communication network (UCN), the system comprising:
 a mediation server coupled to at least a first end point and a second endpoint configured to:
 facilitate exchange of messages and media between the first end point and the second endpoint employing SIP sessions and SDP descriptions; 
 
 the first end point for providing multi-modal communication services through the UCN, the first end point configured to:
 receive a request for invoking a media specific feature; 
 send a SIP re-INVITE that includes an SDP attribute description for the media specific feature to the second end point participating in an established SIP session through the mediation server; and 
 
 the second end point for providing multi-modal communication services through the UCN, the second end point configured to:
 receive the SIP re-INVITE for invoking a media specific feature from the first endpoint; 
 confirm local capability to facilitate the media specific feature; and 
 perform the invoked media specific feature. 
 
 
     
     
       11. The system of  claim 10 , wherein the media specific feature is a music-on-hold feature applicable for a media channel specified by the first end point. 
     
     
       12. The system of  claim 11 , wherein the SDP descriptions associated with the SIP re-INVITE include an originator identified, a session identifier, a session name, a session attribute specifying the music-on-hold feature, and a media channel identifier. 
     
     
       13. The system of  claim 11 , wherein the first end point is further configured to:
 receive a request for clearing the invoked media specific feature; 
 send a SIP re-INVITE that includes another SDP attribute description for the invoked media specific feature to the second end point participating in the established SIP session through the mediation server; and 
 wherein the second end point is further configured to:
 receive the SIP re-INVITE for clearing the invoked media specific feature from the first endpoint; and 
 clear the media specific feature for all channels included in the SIP re-INVITE. 
 
 
     
     
       14. The system of  claim 11 , further comprising a conferencing server configured to:
 in response to receiving the SIP re-INVITE for invoking the media specific feature during a communication session from any participant, issue a SIP re-INVITE to remaining participants for invoking the media specific feature. 
 
     
     
       15. The system of  claim 11 , wherein SDP attribute descriptions for invoking the media specific feature include “a=sendonly” and “a=feature:MoH”, where MoH represents music-on-hold, wherein the SDP attribute description for clearing the media specific feature includes “a=sendrecv” and no description of the feature, and wherein both SDP attribute descriptions include an identification of applicable media channels. 
     
     
       16. The system of  claim 11 , wherein the “sip.rendering” with a “no” value is sent if all media channels contain the media specific feature in the SIP re-INVITE for invoking the media specific feature, and wherein the “sip.rendering” is excluded if no media channels contain the media specific feature in the SIP re-INVITE for clearing the media specific feature. 
     
     
       17. A computer-readable storage medium not consisting of a modulated data signal, the computer-readable storage medium having instructions stored thereon for providing music-on-hold features in a unified communication network (UCN) system, the instructions comprising:
 rendering, at a first communication application, user interface elements for invocation of the music-on-hold feature; 
 upon receiving an invocation of the music-on-hold feature, transmitting to a second communication application a SIP re-INVITE with SDP extensions invoking the music-on-hold feature for an established SIP session; 
 receiving at the first communication application an ACCEPT from the second communication application confirming a capability of a client device executing the second communication application to perform the music-on-hold feature; 
 transmitting a communication invoking the music-on-hold feature; 
 rendering, at the first communication application, additional user interface elements for clearing of the invoked music-on-hold featurel; and 
 upon receiving an indication to clear the invoked music-on-hold feature, transmitting to the second communication application another SIP re-INVITE with SDP extensions clearing the invoked music-on-hold feature for the established SIP session. 
 
     
     
       18. The computer-readable storage medium of  claim 17 , wherein a client device executing the second communication application is not capable of performing the music-on-hold feature without a functioning speaker. 
     
     
       19. The computer-readable storage medium of  claim 17 , wherein the SIP re-INVITE and the another SIP re-INVITE messages include identification of media channels to which the music-on-hold feature is to be applied. 
     
     
       20. The computer-readable storage medium of  claim 17 , wherein the music-on-hold feature includes one of: music streamed from the first communication application and music from a local source of the second communication application.